R E P A I R C O M M A N DE R S C U P O L A ( M 1 1 3 A 2 , M 1 0 6 A 2 , M 1 0 6 4 ,
M 1 2 5 A 2 , A N D M 1 0 6 9 O N L Y)
General Mechanics Tool Kit (Item 35, App B)
Torque Wrench, 1/2 inch drive
Track Vehicle Repairer 63H10
(Item 114, App B)
Commanders cupola removed (page 8-2)
R E M O VE
Lifting or moving objects in
excess of 70 pounds could
injure you. Get an assistant
or a lifting device to help
move armor or other heavy
Improper installation will cause binding
resulting in bearing failure. Block (6)
radius surface must face toward cupola
center. Do not use talcum or other pow-
der residue to reduce friction. When ex-
posed to moisture a chalky substance is
formed causing binding.
1. Turn cupola over. Remove 18 socket head
screws (1), lockwashers (2), and outer
race (3) from hatch (4). Discard lockwashers.
Have helper assist.
Separators are like bearings except for
size and color. Ball bearings are slightly
larger than separators and are white or
cream color. Separators may be any dark
Alternately, install 24 separators (6) and
23 ball bearings (5) between bearing
blocks (7). One separator (6) is to be
installed on each side of each bearing
block (7). A maximum number of sets (one
ball and one spacer per set) is needed
between any two blocks. The number of
sets in each space between blocks must
not differ by more than one set.
2. Remove 140 ball bearings (5), 146 separators
(6), and 6 bearing blocks (7) from inner race
(8). Remove inner race from hatch (4).
lf one ball bearing or separator needs to
be replaced, all ball bearings and separa-
tors must be replaced.
3. Install inner race (8) on hatch (4).
4. Install 140 ball bearings (5), 146 separators
(6), and 6 bearing blocks (7) in groove of
inner race (8).